module: error for CJS .js load within type: module

PR-URL: #29492 Reviewed-By: Jan Krems <jan.krems@gmail.com>

Author: guybedford

lib/internal/modules/cjs/loader.js

@@ -213,16 +213,17 @@ Module._debug = deprecate(debug, 'Module._debug is deprecated.', 'DEP0077');
 // -> a.<ext>
 // -> a/index.<ext>
 
-// Check if the directory is a package.json dir.
-const packageMainCache = Object.create(null);
-// Explicit exports from package.json files
-const packageExportsCache = new SafeMap();
+const packageJsonCache = new SafeMap();
 
-function readPackageRaw(requestPath) {
+function readPackage(requestPath) {
  const jsonPath = path.resolve(requestPath, 'package.json');
- const json = internalModuleReadJSON(path.toNamespacedPath(jsonPath));
 
+ const existing = packageJsonCache.get(jsonPath);
+ if (existing !== undefined) return existing;
+
+ const json = internalModuleReadJSON(path.toNamespacedPath(jsonPath));
  if (json === undefined) {
+ packageJsonCache.set(jsonPath, false);
  return false;
  }
 
@@ -233,45 +234,47 @@ function readPackageRaw(requestPath) {
 
  try {
  const parsed = JSON.parse(json);
- packageMainCache[requestPath] = parsed.main;
- if (experimentalExports) {
- packageExportsCache.set(requestPath, parsed.exports);
- }
- return parsed;
+ const filtered = {
+ main: parsed.main,
+ exports: parsed.exports,
+ type: parsed.type
+ };
+ packageJsonCache.set(jsonPath, filtered);
+ return filtered;
  } catch (e) {
  e.path = jsonPath;
  e.message = 'Error parsing ' + jsonPath + ': ' + e.message;
  throw e;
  }
 }
 
-function readPackage(requestPath) {
- const entry = packageMainCache[requestPath];
- if (entry)
- return entry;
-
- const pkg = readPackageRaw(requestPath);
- if (pkg === false) return false;
-
- return pkg.main;
-}
-
-function readExports(requestPath) {
- if (packageExportsCache.has(requestPath)) {
- return packageExportsCache.get(requestPath);
+function readPackageScope(checkPath) {
+ const rootSeparatorIndex = checkPath.indexOf(path.sep);
+ let separatorIndex;
+ while (
+ (separatorIndex = checkPath.lastIndexOf(path.sep)) > rootSeparatorIndex
+ ) {
+ checkPath = checkPath.slice(0, separatorIndex);
+ if (checkPath.endsWith(path.sep + 'node_modules'))
+ return false;
+ const pjson = readPackage(checkPath);
+ if (pjson) return pjson;
  }
+ return false;
+}
 
- const pkg = readPackageRaw(requestPath);
- if (!pkg) {
- packageExportsCache.set(requestPath, null);
- return null;
- }
+function readPackageMain(requestPath) {
+ const pkg = readPackage(requestPath);
+ return pkg ? pkg.main : undefined;
+}
 
- return pkg.exports;
+function readPackageExports(requestPath) {
+ const pkg = readPackage(requestPath);
+ return pkg ? pkg.exports : undefined;
 }
 
 function tryPackage(requestPath, exts, isMain, originalPath) {
- const pkg = readPackage(requestPath);
+ const pkg = readPackageMain(requestPath);
 
  if (!pkg) {
  return tryExtensions(path.resolve(requestPath, 'index'), exts, isMain);
@@ -372,7 +375,7 @@ function resolveExports(nmPath, request, absoluteRequest) {
  }
 
  const basePath = path.resolve(nmPath, name);
- const pkgExports = readExports(basePath);
+ const pkgExports = readPackageExports(basePath);
  const mappingKey = `.${expansion}`;
 
  if (typeof pkgExports === 'object' && pkgExports !== null) {
@@ -947,6 +950,12 @@ Module.prototype._compile = function(content, filename) {
 
 // Native extension for .js
 Module._extensions['.js'] = function(module, filename) {
+ if (filename.endsWith('.js')) {
+ const pkg = readPackageScope(filename);
+ if (pkg && pkg.type === 'module') {
+ throw new ERR_REQUIRE_ESM(filename);
+ }
+ }
  const content = fs.readFileSync(filename, 'utf8');
  module._compile(stripBOM(content), filename);
 };

src/node_file.cc

@@ -875,7 +875,8 @@ static void InternalModuleReadJSON(const FunctionCallbackInfo<Value>& args) {
  const size_t size = offset - start;
  if (size == 0 || (
  size == SearchString(&chars[start], size, "\"main\"") &&
- size == SearchString(&chars[start], size, "\"exports\""))) {
+ size == SearchString(&chars[start], size, "\"exports\"") &&
+ size == SearchString(&chars[start], size, "\"type\""))) {
  return;
  } else {
  Local<String> chars_string =

test/es-module/test-esm-type-flag-errors.js

@@ -23,6 +23,13 @@ expect('', packageWithoutTypeMain, 'package-without-type');
 expect('--input-type=module', packageTypeModuleMain,
  'ERR_INPUT_TYPE_NOT_ALLOWED', true);
 
+try {
+ require('../fixtures/es-modules/package-type-module/index.js');
+ assert.fail('Expected CJS to fail loading from type: module package.');
+} catch (e) {
+ assert(e.toString().match(/Error \[ERR_REQUIRE_ESM\]: Must use import to load ES Module:/));
+}
+
 function expect(opt = '', inputFile, want, wantsError = false) {
  // TODO: Remove when --experimental-modules is unflagged
  opt = `--experimental-modules ${opt}`;

test/parallel/test-policy-integrity.js

@@ -212,6 +212,10 @@ test({
  shouldFail: false,
  entry: parentFilepath,
  resources: {
+ [packageURL]: {
+ body: packageBody,
+ match: true,
+ },
  [parentURL]: {
  body: parentBody,
  match: true,
@@ -227,6 +231,10 @@ test({
  preload: [depFilepath],
  entry: parentFilepath,
  resources: {
+ [packageURL]: {
+ body: packageBody,
+ match: true,
+ },
  [parentURL]: {
  body: parentBody,
  match: true,
@@ -279,6 +287,10 @@ test({
  shouldFail: false,
  entry: depFilepath,
  resources: {
+ [packageURL]: {
+ body: packageBody,
+ match: true,
+ },
  [depURL]: {
  body: depBody,
  match: true,
@@ -289,6 +301,10 @@ test({
  shouldFail: false,
  entry: depFilepath,
  resources: {
+ [packageURL]: {
+ body: packageBody,
+ match: true,
+ },
  [policyToDepRelativeURLString]: {
  body: depBody,
  match: true,
@@ -309,6 +325,10 @@ test({
  shouldFail: false,
  entry: depFilepath,
  resources: {
+ [packageURL]: {
+ body: packageBody,
+ match: true,
+ },
  [policyToDepRelativeURLString]: {
  body: depBody,
  match: true,
@@ -351,6 +371,10 @@ test({
  shouldFail: false,
  entry: workerSpawningFilepath,
  resources: {
+ [packageURL]: {
+ body: packageBody,
+ match: true,
+ },
  [workerSpawningURL]: {
  body: workerSpawningBody,
  match: true,
@@ -370,6 +394,10 @@ test({
  entry: workerSpawningFilepath,
  preload: [parentFilepath],
  resources: {
+ [packageURL]: {
+ body: packageBody,
+ match: true,
+ },
  [workerSpawningURL]: {
  body: workerSpawningBody,
  match: true,

test/parallel/test-policy-parse-integrity.js

@@ -36,8 +36,16 @@ if (!tmpdirURL.pathname.endsWith('/')) {
  tmpdirURL.pathname += '/';
 }
 
+const packageFilepath = path.join(tmpdir.path, 'package.json');
+const packageURL = pathToFileURL(packageFilepath);
+const packageBody = '{"main": "dep.js"}';
+
 function test({ shouldFail, integrity }) {
  const resources = {
+ [packageURL]: {
+ body: packageBody,
+ integrity: `sha256-${hash('sha256', packageBody)}`
+ },
  [depURL]: {
  body: depBody,
  integrity